Judge Kristine Baker granted a preliminary injunction to block the law, which was passed by the GOP majority legislature, signed by Republican governor Asa Hutchinson and set to go into law on 28 July.
The sweeping ban allowed an abortion to save the life of the mother in a medical emergency, but did not provide any exception in the case of rape or incest.
Judge Baker will hear a legal challenge to it but called the law “categorically unconstitutional” since it would ban the procedure before the foetus is considered viable.
“Since the record at this stage of the proceedings indicates that women seeking abortions in Arkansas face an imminent threat to their constitutional rights, the Court concludes that they will suffer irreparable harm without injunctive relief,” she wrote in her judgement.
Following Donald Trump’s appointments to the US Supreme Court, Republican lawmakers in a string of states introduced new abortion laws.
The Supreme Court has announced that it will hear a case about whether states can ban abortions before a foetus can survive outside the womb.
“Today’s decision makes clear that Arkansas’ abortion ban is just as unconstitutional as the bans struck down before it in states like Kentucky, Alabama, Ohio, Georgia, and Missouri, and ensures that abortion remains legal in Arkansas, as it is in all 50 states,” said Meagan Burrows, staff attorney at the ACLU Reproductive Freedom Project.
“Arkansas pursued a clearly unconstitutional law that would disproportionately harm people of color, people who live in rural areas, and people with low incomes — all of whom already face significant barriers to accessing health care and higher risks of pregnancy-related death.
“The court’s ruling today should serve as a stark reminder to anti-abortion politicians in Arkansas and other states that they cannot strip people of their right to make the deeply personal decision about whether to have an abortion or continue a pregnancy.
“We’ll continue to fight to make sure abortion stays legal in Arkansas and that the state’s unconstitutional ban is struck down for good.”